import React, {Component} from 'react';
//引入store用于获取redux中保存的状态
import store from "../../redux/store";

class Count extends Component {

    // componentDidMount() {
    //     // 检查redux中状态的变化，只要变化，就调用render
    //     store.subscribe(() => {
    //         this.setState({});
    //     })
    // }

    increment = () => {
        const {value} = this.selectNumber;
        store.dispatch({type: 'increment', data: value * 1})
    }

    decrement = () => {
        const {value} = this.selectNumber;
        store.dispatch({type: 'decrement', data: value * 1})
    }

    incrementIfOdd = () => {
        const {value} = this.selectNumber;
        const count = store.getState();
        if (count % 2 !== 0) {
            store.dispatch({type: 'increment', data: value * 1})
        }
    }

    incrementAsync = () => {
        setTimeout(() => {
            const {value} = this.selectNumber;
            const count = store.getState();
            store.dispatch({type: 'increment', data: value * 1})
        }, 500)
    }

    render() {
        return (
            <div>
                <h1>当前求和为：{store.getState()}</h1>
                <select ref={c => this.selectNumber = c}>
                    <option value="1">1</option>
                    <option value="2">2</option>
                    <option value="3">3</option>
                    <option value="4">4</option>
                </select>&nbsp;
                <button onClick={this.increment}>+</button>
                &nbsp;
                <button onClick={this.decrement}>-</button>
                &nbsp;
                <button onClick={this.incrementIfOdd}>当前求和为奇数</button>
                &nbsp;
                <button onClick={this.incrementAsync}>异步求和</button>
                &nbsp;
            </div>
        );
    }
}

export default Count;